Scientist. Russian chemist who developed the periodic classification of the elements. He was the youngest child out of 14 born in the small Siberian town of Tobolsk. His father became blind in the year of Dmitry's birth and died in 1847. To support the family, his mother ran a small glass factory owned by her family in a nearby town. After the factory burned down, the family moved to St. Petersburg, where Mendeleev enrolled in the Main Pedagogical Institute. He received a master's degree in 1856 and began to conduct research in organic chemistry. Mendeleev discovered that if all the known chemical elements were arranged in order of increasing atomic weight, the resulting table displayed a recurring pattern of properties within groups of elements. This became known as Mendeleev Periodic Table of Elements. The table had the gaps in places where he believed unknown elements would find their place. He even predicted the likely properties of some of the potential elements. The subsequent proof of many of his predictions within his lifetime brought him fame as the founder of the periodic law. After the defense of his doctoral dissertation in 1865 he was appointed professor of chemical technology at the University of St. Petersburg, where he continued to teach until 1890. By the time Mendeleev died in 1907, he enjoyed international recognition and had received distinctions and awards from many countries. He is credited with discovering the Russian vodka recipe where the ideal proportion of water and alcohol is of 40 degrees and received a patent for Mendeleev's vodka from the Russian government in 1894. He is also given credit for the introduction of the metric system to the Russian Empire. Element number 101, the radioactive mendelevium, is named after him.